Last edited 11 Feb 2021


A tree is a plant that is characterised by its elongated stem, or trunk, supporting branches, and (in most species) leaves. Trees can vary greatly depending on geographic region and climate. Trees can live for a long time, some for thousands of years.

Trees absorb carbon dioxide during their growth and store it until they decay or are burned. This makes timber a sustainable material, as its net environmental impact is zero (excluding processing, transport etc impacts).

In case law a tree has been defined for planning purposes as anything that would ‘ordinarily be regarded as a tree. Thus, it would not include a shrub, a bush or scrub.’

Trees can be protected in law by tree preservation orders, or by being in a conservation area. In this case, a tree is considered to be a stem with a diameter of more than 75mm when measured at 1.5 metres up the stem. For more information see: Definition of tree for planning purposes.

The glossary to the National Planning Policy Framework defines an ancient tree or veteran tree as: 'A tree which, because of its age, size and condition, is of exceptional biodiversity, cultural or heritage value. All ancient trees are veteran trees. Not all veteran trees are old enough to be ancient, but are old relative to other trees of the same species. Very few trees of any species reach the ancient life-stage.'

Articles about trees on Designing Buildings Wiki include:

Designing Buildings Anywhere

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